NBC is using the final days of the Winter Olympics to debut two family comedies, neither of which live up to their moderately high concepts.

"About a Boy," which premieres Saturday before moving to Tuesdays, is based on the 2002 film of the same name starring Hugh Grant, which was based on the 1998 book of the same name by Nick Hornby.

And there's the problem right there: A set-up and narrative diluted by overuse, time and the inevitable salt-water saturation that occurs whenever a story moves out of coolly clever British fingers into the softer nest of American hands.

In this case, those hands belong to the talented Jason Katims ("Friday Night Lights," "Parenthood"). If anyone could make this questionable idea work, it's Katims, but he seems to have met his match. Within two minutes of the pilot's opener, I found myself pining for Hugh Grant, an event that seemed impossible up until the moment it occurred.

It's not so much Grant I miss, it's the slow and subtle build of a man who seems to have the perfect life — lots of money, no responsibilities, really good hair — until he meets an odd yet lighthearted child who makes him realize that freedom is, as we have been told before, just another word for nothing left to lose.

This "About a Boy" is as subtle as a chain saw. Meet Will Freeman (David Walton), a guy so mid-life selfish that he calls his friend's baby "it." He also lies about having not just a kid, but one who survived cancer, in order to sleep with the comely single mom he has pounced on in the street.

As luck would have it, wacky Fiona (Minnie Driver) and her son, Marcus (Benjamin Stockham), have moved next door That Very Day. Marcus is presented as a classic weird kid, despite the fact that the hallmarks of this weirdness — colorful sweaters, veganism, adult syntax — are pretty standard among kids on TV these days.

But Marcus needs to be perceived as weird because he needs to be bullied and he needs to be bullied so he has a reason to run into Will's house one day. Once there, Will can then palm him off as the kid he doesn't have.

Before realizing, of course, that Marcus has feelings too, and life is more than just doing precisely what you want every minute of the day.

And that is how each of the first three episodes unfurls. Will acts selfish, Fiona — also made to seem somehow "weird" because she doesn't approve of Will running into the street in his underpants to remind his "date" that she owes him an orgasm — calls him on it, and then Marcus shows him the importance of putting others first.

Katims has promised that, this being San Francisco, some of the characters from "Parenthood" may wander by, but what "About a Boy" really needs is Tami Taylor from "Friday Night Lights" to talk some sense into everyone and then sit them down for a dinner in which no one treats seitan like it is something previously unheard of. In San Francisco.

"Growing Up Fisher," which debuts Sunday before moving to Tuesdays, is a similar muddle of perfectly good parts. Creator D.J. Nash ("Up All Night," "Guys With Kids") has shamelessly stacked the deck — a blind dad played by J.K. Simmons, a "Wonder Years"-like narration by Jason Bateman — but once again the "man 'n' boy learn life lessons together" is dropped on the viewer's head like an Acme anvil.

The exploits of a blind dad who has spent years passing for sighted not being enough, "Growing Up Fisher" opens with young Henry (Eli Baker) realizing that his parents, Joyce (Jenna Elfman) and Mel (Simmons), are getting a divorce.

The kindest, gentlest divorce in the history of nuptial dissolution, it must be added. The problem, apparently, is that Joyce married Mel "too young," i.e. when she got pregnant with Henry's older sister, Katie (Ava Deluca-Verley); now she wants to redo the young adulthood she missed.

Almost 20 years divides Simmons and Elfman and she's clearly playing even younger, so that unplanned pregnancy is a tiny bit worrisome (please God don't let a future episode reveal he was her father's best friend). Still the interplay between Joyce and Katie, who wants her mother to act like an adult, is the best thing about the show.

Unfortunately, this isn't the A-plot, which revolves more around Mel and Henry, especially Henry. How he's feeling about the divorce, his father's new guide dog, girls, his mom's decision to smoke a pipe (my kingdom for a mom not forced to seem wacky!), whatever.

Simmons is great as he always is, but between the divorce, the mid-life crisis, the coming out as blind, the mother-daughter tension and the boy discovering his true self and The Importance of Family, there is simply too much to look at and not enough to see.

With the notable exception of those breathless minutes in which U2 and members of the Rutgers Marching Band seemed to be standing way too close to the edge of the top of Rockefeller Center, the debut of "The Tonight Show with Jimmy Fallon" was conspicuously, and seemingly consciously,...